This invention relates to generating and accumulating status information associated with a data processing operation.
For example, in a vector operation (in which the same steps--e.g., add, multiply, accumulate--are performed on all data elements of the vector) it is useful to generate and accumulate the status (e.g., overflow, underflow, result) of each step to aid subsequent generation of exception conditions The status information typically is generated in a standard (e.g., IEEE 754) format.
Status information may be accumulated on a step by step basis and assembled as a status word (indicating the status of each step). In the case of a complex algorithm, e.g. for a vector operation, many steps are needed to produce a result, and the user typically does not need to know that a given step caused an overflow but only whether an overflow (or other exception) was generated somewhere among the steps that led to a particular result.
Sometimes status for a vector operation is generated by including, in the vector algorithm, microcode instructions to specify when status should be accumulated.